Engineering Review | Facilities Review Application

Approval to Construct

An Approval to Construct (ATC) is a certificate issued by ADEQ or a delegated authority that allows an applicant to construct, modify, or make an alteration that will affect the treatment, capacity, water quality, flow, distribution or operational performance of a public water system.

The primary components necessary for an ATC application are:

  • ATC Application
  • Fee
  • Construction Plans/Drawings
  • Design Report
  • New Source Analysis (for new well or new source only)
  • Notice of Intent to drill (for new well only)
  • Water Service Agreement (if water source is provided by someone other than applicant)
  • ATC Application Form | Download >

ATC Design Report and Construction Drawing Examples

ADEQ as created examples of a design report and construction drawings for use as a guidance document when filling out your ATC Application. Other agencies, cities, counties, contractors, developers, and other entities may require different or additional criteria and should be referenced accordingly.

The following examples show the minimum criteria needed for submittal to ADEQ:

Approval of Construction

An Approval of Construction is a certificate issued by ADEQ or a delegated authority that allows an applicant to operate a public water distribution system after construction and final testing have been completed. A professional engineer registered in Arizona must complete a final inspection and submit a Certificate of Completion to confirm that the construction conforms to approved plans. 

The primary components necessary for an AOC application are:

  • As-Built Plans
  • Pressure/Leakage Testing Results
  • Disinfection Testing Results
  • Bacteriological Testing Results
  • Operations and Maintenance Manual (new treatment only)

AOC Application Form | Download >

Design Standards

Several material, construction and testing standards are referenced by rule for drinking water systems. Commonly utilized standards referenced by rule include:

  • Engineering Bulletin 8 — Disinfection of Water Systems | Download >
  • Engineering Bulletin 10 — Guidelines for the Construction of Water Systems | Download >

Other system designs may be approved if the applicant can demonstrate that the system functions properly and may be operated reliably in compliance with Arizona Administrative Code (AAC) Title 18, Chapter 5. Some standards may be from:

  • Maricopa Association of Governments (MAG): Standard Specifications & Details Committee | View Website >
  • Pima County and City of Tucson: Standard Specifications and Standard Details for Public Improvements | View Website >
  • American Society for Testing and Materials (ASTM) International | View Website >
  • American Water Works Association (AWWA) | View Website >
  • National Sanitation Foundation (NSF) | View Website >


View our list of frequently asked questions and answers | View >